In 1964 which major disease spread in Bangladesh?

The 1961–1975 cholera pandemic (also known as the seventh cholera pandemic) was the seventh major outbreak of cholera and occurred principally from the years 1961 to 1975; the strain involved persists to the present.[1] This pandemic, based on the strain called El Tor, started in Indonesia in 1961 and spread to East Pakistan, which is now Bangladesh by 1963.[2] Then it went to India in 1964, followed by the Soviet Union by 1966. In July 1970, there was an outbreak in Odessa and in 1972 there were reports of outbreaks in Baku, but the Soviet Union suppressed this information.[2] It reached Italy in 1973 from North Africa. Japan and the South Pacific saw a few outbreaks by the late 1970s.[2] In 1971, the number of cases reported worldwide was 155,000. In 1991, it reached 570,000.[1] The spread of the disease was helped by modern transportation and mass migrations. Mortality rates, however, dropped markedly as governments began modern curative and preventive measures. The usual mortality rate of 50% dropped to 10% by the 1980s and less than 3% by the 1990s.[1]